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348 CLARK. G.M. ET AL. ORIGINAL ARTICLES MULTIPLE-CHANNEL COCHLEAR IMPLANTS FOR CHILDREN: THE MELBOURNE PROGRAM CLARK, O.M., DAWSON, P.W., BLAMEY, P.I, DETTMAN, S.J., ROWLAND, L.C., BROWN,A.M., DOWELL, R.C., PYMAN, B.C., WEBB, R.L. Australian Bionic Ear and Hearing Research Institute, Human Communication Research Centre, University of Melbourne and Cochlear Implant Clinic, Royal Victorian Eye and Ear Hospital, Melbourne. Although there have been 300 years of deaf education, may be taught the Australian version of sign language of profoundly-totally deaf children today on average are not the deaf (Auslan). In the case of signed English, the signs able to reach the same level of achievement as their represent individual words as well as conveying grammatical normally hearing peers (Geers & Moog, 1989). This failure information such as tense. This form of signing is used in of deaf children to develop their true potential is largely total communication. and although it is difficult for due to the difficulty they have in communicating with children to attend to the speech signal by the auditory/oral normally hearing people. During the last 300 years there mode at the same time as signed English, they can develop have been basically two different methods of education the skills to communicate by either one used separately. used (The New Encyclopaedia Britannica, 1983). Firstly, In the case of the sign language of the deaf, the one which maximises auditory and lip reading cues grammatical structure is quite different from the structure (auditory/oral), advocated by Juan Pablo Bonet (1620), and of English. In practice, this method makes it difficult to one which uses a series of signs to convey meaning learn written language, and is not appropriate for (signing), developed by Charles-Michel (1712-89). In combining with an auditory/oral method of education. addition, there is a method which endeavours to combine As the multiple-channel cochlear implant provides both auditory/oral and signing approaches called total information by stimulating hearing sensations, it is communication. In practice, however, children taught by optimally used by combing these auditory signals with lip total communication tend to receive speech more reading cues. Consequently, children receiving a cochlear predominantly by one or other of these methods. implant should ideally be educated using an auditory/oral Within the two main methods are variations. For method. example, with the auditory/oral system some educators prefer to teach by combining auditory information with lip reading cues while others endeavour to get children to Management Team develop their listening skills by withholding visual information (the auditory/verbal method). A further In managing a child for a cochlear implant we consider variation of the auditory/oral method is to use cueing that a team approach is essential. The management team supplements. In this situation the child is helped by is outlined in Figure l. The team consists of otologists, providing additional visual cues when speech sounds look audiologists, speech pathologists, educators of the deaf, the same on the lips. There are also different approaches and consultants in psychology, child psychiatry and social to training with the auditory/oral schemes. On the one hand, educators may emphasize training in listening to segments of speech and speaking in very structured - Otologists situations. On the other hand, they may emphasize learning conversational speech in more natural and unstructured - Audiologists ways similar to that which would occur with normally - Speech pathologists hearing children. - Educators of the deaf In the case of signing there are basically two different - Consultants systems: children may be taught signed English, or, they - Psychologists - Child psychiatrists Correspondence: - Social workers Professor Graeme M. Clark, Royal Victorian Eye and Ear Hospital, FIG. 1. Management team personnel; cochlear implants for children. 32 Gisborne Street, East Melbourne. Victoria 3002 J. 01OLARYNG. soc. AUSTRAL.. JANUARY 1991, 6. No.5 !i!!!!l'I .... ,......,---- -~ CLARK, G.M. ET AL. 349 work. The team also requires a leader who is co!1versant establishing the hearing threshold levels and determining with most aspects of the program. Furthermore, there is how effective the hearing aids are. Establishing the hearing a need for very good liaison between members of the team thresholds in very young children is facilitated by using a based in a hospital and the teachers in the school. The team steady state evoked response (SSEP) technique we have is responsible for the following areas in a cochlear implant developed in the Department of Otolaryngology (Rickards child's management: preoperative evaluation and selection; & Clark, 1984). This technique involves presenting parent counselling; surgery; auditory training in speech amplitude modulated (AM) and/or frequency modulated production, language and auditory perception and (FM) sounds with different carrier frequencies. A Fourier audiological assessment. These responsibilities are listed analysis is carried out on the evoked responses, and in Figure 2. objective criteria are set for establishing thresholds at each caI'Tier frequency. The thresholds are specific for the regions excited by the carrier frequencies. It is an especially useful procedure in measuring the thresholds for low frequencies - Preoperative evaluation and which can still be present when the high frequencies are selection lost. Assessing hearing thresholds at low frequencies is - Parent counselling difficult with standard ABR techniques, but can be successfully carried out using the SSEP procedure referred -Surgery to above. - Auditory training In stages 3 and 4, we assess all aspects of a child's ability - Audiological assessment to communicate. This means assessing speech perception, speech production, language skills and pragmatics (their ability to converse). Following this speech and language assessment, the FlG. 2. Management team - responsibilities: cochlear implants jar children undergo a preoperative training program so they children. can learn to use any residual hearing. This program also gets them used to the auditory/oral training they will receive when they get an implant. Preoperative Evaluation and Selection Finally, the assessment of the child is reviewed by the management team and ethics committee before The preoperative evaluation and selection process takes implantation. place in five stages. At any stage a child may be considered unsuitable for an implant, and may be referred for an alternative sensory aid. The stages are shown in Figure 3. Parent Guidance SI8ge 1: Initial assessment We would like to emphasize that, preoperatively and Hisiory (pmllmlnary) Audlomolry postoperatively, the parents need counselling. This help ~ includes information on the procedure and discussion of Siage 2: AkdlCIIIllnve.llgatlons HI.tory (""ta/Ied) their emotions during both the preoperative and Physical examInation Radiology postoperative periods. The clinician has a responsibility to PromonlQfy sUmulatlon .......r.!!- address with the parent such issues as the potential and Stage 3: AudJDIOfjlcaJ evaluations limitations of the device, the range of results obtained with E=:~:::'::':::i:S ~ Speech percepllon ttnlting Preoperative training. children who currently have the implant, the importance _~ Family support, Stage 4: SpeeCh and I8nguage evaluation, EducBti()(UIllia/son of factors such as motivation (the child's and their own), Speech production ......:::t:J- and the effect of age at onset of deafness and current Language Pragmatic behaviour development of speech and language on the child's Stage 5:-""- Clinical review prognosis. Time is needed to help the parents understand --J!!!!I"'~ SUrgery and accept the effects of implantation. The time available PoatopIJrativs management before the operation is a valuable time for developing FIG. 3. Preoperative evaluation and selection; cochlear implantsjor rapport with the parent. children. Parents are also encouraged to have contact with parents of children who have already received the implant. This The first stage consists of an initial medical assessment, is accomplished through the Parents' Support Group which audiometric testing of hearing thresholds, and general meets on a six-weekly basis. This forum allows parents to counselling to ensure that the parents' expectations are develop friendships and sources of information: valuable realistic. support in times of need. Luterman (1979, 1984) notes that The second stage consists of a detailed clinical history the most valuable service a professional can give a parent and examination. We pay particular attention to middle ear is to put them in touch with other parents. The parents infections, as susceptibility to infection may delay or themselves recognise the value of sharing experiences and prevent implantation. A CT scan is carried out under emotions, and supporting each other. anaesthesia for young children. Electrical stimulation of An important component of the preoperative period is the promonotory is only done for children 10 years and preparing the child for the operation. The parents may be above. reluctant to talk with their child about the operation, In stage 3, the audiological assessment aims at fearing the child may become anxious about the events. J. OTOLARYNG. soc. AUSTRAL., JANUARY 1991, 6, No.5 350 CLARK, GS1. ET At. They need to be encouraged to discuss the events